I agree that it is in Airbnb’s best interests to help assure their listings are clean. Upselling cleaning services isn’t a bad idea. However, Airbnb would then have to get involved with the quality of the services, theft, insurance, dependability of the services, etc., and the customer service support for all of that. Probably not in Airbnb’s list of priorities.
@Daniel2962 Last year, I proposed that the Community Center consider adding a new message board for classified ads for needs and services such as cleaning and co-hosting, but it didn't pan out. You could try the German-language message board or see if there's a social media group for Munich homesharers to ask for recommendations.
Airbnb itself is not going to be involved with connecting you to local services, though. That's way outside the scope of what they offer as a listing service.